Question : Outlook 2007 hangs while sending large emails (only over HTTPS, not over VPN or while on LAN)

Hey all,

I've got a customer with a very curious problem.  After a reboot of the server, people outside of the office using Outlook 2007 (connecting via Outlook Anywhere/RPC over HTTPS) are unable to send large emails.  

The server is Exchange 2003 SP2 running on an SBS 2003 SP2 R2 box.  The two clients I've tried are both Outlook 2007 SP2.

Here's what I've tested in Outlook:

* Sending emails of any size when connected via VPN works fine
* Sending test emails (under 10k) via RPC over HTTPS works
* Sending larger emails (around 1MB - doesn't matter if it's 1MB of plain text or a 1MB zip attachment) simply hangs for at least 30 minutes until I kill it.  I've turned on Outlook logging and posted the contents below.
* Receiving email seems to be fine via VPN or RPCoHTTPS

Here's an example of the OMPLog.log file:

2010.06.18 17:06:12 <<<< Logging Started (level is LTF_TRACE) >>>>
2010.06.18 17:06:12 HELPER::Initialize called
2010.06.18 17:06:12 Initializing: Finding a Transport
2010.06.18 17:06:12 MAPI XP Call: XPProviderInit in EMSMDB.DLL, hr = 0x00000000
2010.06.18 17:06:12 MAPI XP Call: TransportLogon, hr = 0x8004011d
2010.06.18 17:06:12 MAPI XP Call: Shutdown, hr = 0x00000000
2010.06.18 17:06:12 MAPI XP Call: XPProviderInit in EMSMDB.DLL, hr = 0x00000000
2010.06.18 17:06:14 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:06:14 MAPI XP Call: TransportLogon, hr = 0x00000000
2010.06.18 17:06:14 Initializing: Found a transport, Error code = 0x00000000
2010.06.18 17:06:14 MAPI XP Call: AddressTypes, hr = 0x00000000, cAddrs = 3, cUids = 1
2010.06.18 17:06:14 MAPI XP Call: RegisterOptions, hr = 0x00000000, cOptions = 2
2010.06.18 17:06:14 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:06:14 MAPI XP Call: TransportNotify(BEGIN_IN|BEGIN_OUT), hr = 0x00000000
2010.06.18 17:06:14 HELPER::Initialize done, Error code = 0x00000000
2010.06.18 17:06:14 HELPER::GetCapabilities called, Error code = 0x00000000
2010.06.18 17:11:26 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:11:28 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:14:06 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:14:08 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:19:30 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:19:33 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:22:05 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:22:08 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:25:06 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:25:08 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:28:10 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:28:13 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:34:40 MAPI Status: (-- -- ---/--- -- ---)
2010.06.18 17:34:43 MAPI Status: (IN -- ---/OUT -- ---)
2010.06.18 17:37:41 MAPI Status: (-- -- ---/--- -- ---)

I've checked in IIS and RPCProxy.dll exists in Web Extensions, with the correct path, and seems to match the size and date of the same file on other SBS 03 customers I support.

Any ideas?

Answer : Outlook 2007 hangs while sending large emails (only over HTTPS, not over VPN or while on LAN)

We've done some further investigation and confirmed this is an AVG issue.  

The AVG client (Business Edition 9) includes an "Online Shield" service, which innocuously claims to protect Web and Instant Messaging traffic.  Last month the client had upgraded from 8.5 to 9.0 and restarted the server (no problems yet).  After the 2nd restart last week, the problem arose.

While we had an Outlook session open to the server over SSL, we turned this service off in AVG and every Outlook connection issue resolved within a couple seconds.

I'd recommend disabling this service (and other "client PC" intended modules like LinkScanner) in AVG 9.  

Note: this module is available in every version of AVG 9 (Business edition, Internet Security, etc.) with the possible exception of "Free".